Sweet potatoes and oatmeal were other ingredients in the food my wife made.
Chicken is something that dogs are commonly allergic to from my wife's research. Turkey is better, the kibble we feed ours is turkey and sweet potato.
We do switch up the protein to what may be on sale. We've done Turkey in the past also. Chicken, if your dog is able to eat it, is usually the least expensive way to go. Sweet potatoes are a good add in but we were told to always skin them.